空气污染和二氧化氮的监测及趋势（2005 – 2014）

NO2 concentrations in Asia between 2005 and 2014, with the blue indicating 0 and the red indicating 5,000 trillion molecules per cubic centimeters; China has witnessed an expansion of high NO2 pollution. [Images: NASA]

Using new, high-resolution global satellite maps of air quality indicators, NASA scientists tracked air pollution trends over the last decade in various regions and 195 cities around the globe. According to recent NASA research findings, the United States, Europe and Japan have improved air quality thanks to emission control regulations, while China, India and the Middle East, with their fast-growing economies and expanding industry, have seen more air pollution.

Scientists examined observations made from 2005 to 2014 by the Ozone Monitoring Instrument aboard NASA’s Aura satellite. One of the atmospheric gases the instrument detects is nitrogen dioxide, a yellow-brown gas that is a common emission from cars, power plants and industrial activity. Nitrogen dioxide can quickly transform into ground-level ozone, a major respiratory pollutant in urban smog. Nitrogen dioxide hotspots, used as an indicator of general air quality, occur over most major cities in developed and developing nations. Read more…

The trend map of East Asia shows the change in NO2 concentrations from 2005 to 2014, with apparent drops in Beijing, Shanghai and Guangzhou metropolitan areas (blue). [Image: NASA]

China, the world’s growing manufacturing hub, saw an increase of 20 to 50 percent in nitrogen dioxide, much of it occurring over the North China Plain. Three major Chinese metropolitan areas — Beijing, Shanghai, and the Pearl River Delta — saw nitrogen dioxide reductions of as much as 40 percent.

Here below is a video from NASA about the human fingerprint on global air quality: